First-grader Soumia Chetouane has never heard of a vegan. But she thinks she knows something about vegetarians.

"If one of your dogs is sick, that's where you go," Soumia, 6, said as she munched cheese pizza yesterday at Glen Forest Elementary School in Falls Church.

Soumia may not know what a meat-free diet is called. But if she and her friends ever decide to go vegetarian or vegan, they're in the right school system.

This week, the Physicians Committee for Responsible Medicine, a District-based group that promotes a vegan diet (one that excludes all animal products) and healthful, low-fat food options for children, awarded the Fairfax County school system an A in its School Lunch Report Card. None of the other 17 large U.S. school systems the group surveyed scored as high.

"Everybody is responsive to the childhood obesity epidemic, but Fairfax really pulled out all the stops," said Jeanne Stuart McVey, a spokeswoman for the group.

The Montgomery County schools, the only other local system in the report card, received a B.

The committee examined about a month's worth of menus from the school districts, checking how often vegan or vegetarian entrees were offered, policing vending machines for high-fat snacks and measuring whether menu items met U.S. Department of Agriculture requirements. Fairfax has vegan options, and the county got a boost because students can buy soy milk for 75 cents.

Replacing the traditional fried chicken nuggets and greasy pizza with more healthful options has become a priority in many school districts because too many children are putting on too much weight.

Whether Soumia and her peers actually eat healthful school lunches is open to question. She had chocolate milk and a frozen orange-flavored snack with her pizza. Other students in the cafeteria nibbled at side salads and chilled pears in a bowl. But how many kids will bypass chocolate milk when it's offered?

According to the federal Centers for Disease Control and Prevention, about 16 percent of children ages 6 to 11 were overweight in 2002, up from 7 percent in 1980. For youths ages 12 to 19, the percentage who were overweight tripled between 1980 and 2002, to 16 percent. With the extra pounds comes an increased risk of such health problems as diabetes and, later in life, heart disease and stroke.

Fairfax school officials have sought in recent years to get more fruit, vegetables and whole grains onto lunch trays.

"I think we should have an A because when it comes to nutrition and nutrition education, we've been a leader for years," said Penny McConnell, food and nutrition director for the Fairfax schools. She banished Little Debbie snack cakes from vending machines and even persuaded students to snack on jicama sticks. She gave traditional Oreos the boot but let Oreo Thins -- at 100 calories a pack -- stay.

Still, McConnell said, though she ensures that there are choices for students who are vegetarian or vegan, her menus are also filled with lean meats, yogurt and low-fat cheeses.

"I don't support forcing the vegan option on every person," McConnell said. "We have a right to choose."

Kathy Lazor, director of food and nutrition for the Montgomery schools, said her system was unfairly penalized because it doesn't serve soy milk. Instead, she said, students can opt for 100 percent fruit juice or water.

Lazor said the Montgomery schools are working with the United Soybean Board to get more soy products into cafeterias. In the past, though, Montgomery students rejected soy burgers that were supposed to taste like chicken.

Students in both counties increasingly are eating lean hamburgers on whole-wheat buns. As for those cinnamon buns in Montgomery cafeterias -- they're whole-grain.

Fairfax middle school students may be distressed to find that french fries, which used to be served three times a week, have been banned. But that doesn't mean the choices aren't tasty. At Glen Forest Elementary yesterday, 6-year-old Ousama Chatib had cheese pizza, chocolate milk and a cup of minestrone.